The proposed project will continue the studies on the effects of copper deficiency on animal metabolism. In particular the studies will be directed toward determining the cause of the sialic acid decrease in erythrocyte membranes and the physiological significance of this decrease in the life span of the erythrocytes. In addition studies will be undertaken to isolate and characterize the chelators present in the mucosa which bind copper and to establish their importance in absorption. The increase in the lipid content of the aorta in copper deficiency will be more fully characterized and studies will be undertaken to determine the biochemical cause of the increase. Further studies will be undertaken on the lack of response to glucocorticoids in enzyme induction in copper deficiency. Further studies will be undertaken on the effect of copper deficiency on calcification of the aorta with particular attention being paid to the role of the epsilon amino groups of lysine.